二进制值和十六进制字符串相互转换的C++代码

 1 #include <iostream>
 2 #include <string>
 3 #include <stdint.h>
 4 
 5 using namespace std;
 6 
 7 string BinToHex(const string &strBin, bool bIsUpper = false)
 8 {
 9     string strHex;
10     strHex.resize(strBin.size() * 2);
11     for (size_t i = 0; i < strBin.size(); i++)
12     {
13         uint8_t cTemp = strBin[i];
14         for (size_t j = 0; j < 2; j++)
15         {
16             uint8_t cCur = (cTemp & 0x0f);
17             if (cCur < 10)
18             {
19                 cCur += '0';
20             }
21             else
22             {
23                 cCur += ((bIsUpper ? 'A' : 'a') - 10);
24             }
25             strHex[2 * i + 1 - j] = cCur;
26             cTemp >>= 4;
27         }
28     }
29 
30     return strHex;
31 }
32 
33 string HexToBin(const string &strHex)
34 {
35     if (strHex.size() % 2 != 0)
36     {
37         return "";
38     }
39 
40     string strBin;
41     strBin.resize(strHex.size() / 2);
42     for (size_t i = 0; i < strBin.size(); i++)
43     {
44         uint8_t cTemp = 0;
45         for (size_t j = 0; j < 2; j++)
46         {
47             char cCur = strHex[2 * i + j];
48             if (cCur >= '0' && cCur <= '9')
49             {
50                 cTemp = (cTemp << 4) + (cCur - '0');
51             }
52             else if (cCur >= 'a' && cCur <= 'f')
53             {
54                 cTemp = (cTemp << 4) + (cCur - 'a' + 10);
55             }
56             else if (cCur >= 'A' && cCur <= 'F')
57             {
58                 cTemp = (cTemp << 4) + (cCur - 'A' + 10);
59             }
60             else
61             {
62                 return "";
63             }
64         }
65         strBin[i] = cTemp;
66     }
67 
68     return strBin;
69 }
70 
71 int main()
72 {
73     string strBin = "!@#$%^&*()_+~`1234567890-=";
74     string strHex = "21402324255E262A28295F2B7E60313233343536373839302D3D";
75 
76     string strBinToHex = BinToHex(strBin);
77     cout << strBinToHex << endl;
78     strBinToHex = BinToHex(strBin, true);
79     cout << strBinToHex << endl;
80 
81     string strHexToBin = HexToBin(strHex);
82     cout << strHexToBin << endl;
83 
84     return 0;
85 }